Sealing system for refrigeration cassette

ABSTRACT

A refrigerated merchandiser ( 10 ) includes a cabinet ( 20 ) having a top wall ( 22 ), a lower wall ( 24 ), a rear wall ( 34 ), and side walls ( 36, 38 ) defining an interior product display space ( 100 ) housing a product ( 110 ) in a refrigerated environment for consumer selection. A refrigeration unit ( 50 ) is disposed in operative association with the interior product display space in a compartment ( 55 ) beneath the lower wall ( 24 ). A first opening in the lower wall provides an air return inlet ( 102 ) establishing a flow passage from the interior product display space ( 1000  to the compartment ( 55 ) beneath the lower wall. A sealing member ( 58 ) is disposed between the under surface of the lower wall ( 24 ) and the upper surface of the refrigeration unit cassette ( 50 ) about the first opening; and a positioning apparatus ( 150 ) for raising the refrigeration unit cassette ( 50 ) unit into sealing relationship with the lower wall.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser. No. 60/662,960, filed Mar. 18, 2005, and entitled CAM COMPRESSION MECHANISM FOR GASKET SURFACES FOR REFRIGERATION CASSETTE AND CABINET DESIGNS, which application is incorporated herein in its entirety by reference.

This application is related to the following applications subject to assignment to the common assignee of this application and filed with the United States Patent and Trademark Office on the same date as this application:

-   U.S. patent application Ser. No. ______ (Attorney Docket No.     210_(—)817NP), entitled “REFRIGERATED MERCHANDISER ”; -   U.S. patent application Ser. No. ______ (Attorney Docket No.     210_(—)820NP), entitled “MODULAR REFRIGERATION CASSETTE ”; -   U.S. patent application Ser. No. ______ (Attorney Docket No.     210_(—)879NP), entitled “MODULAR REFRIGERATION CASSETTE WITH     CONDENSATE EVAPORATIVE TRAY ”; -   U.S. patent application Ser. No. ______ (Attorney Docket No.     210_(—)818NP), entitled “BOTTOM DECK ASSEMBLY FOR REFRIGERATED     MERCHANDISER ”; and -   U.S. patent application Ser. No. ______ (Attorney Docket No.     210_(—)819NP), entitled “EVAPORATOR FAN/MOTOR ASSEMBLY MOUNTING     BRACKET ”.     Each of the afore-listed patent applications is incorporated herein     by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to refrigerated merchandisers in general and, more particularly, to a refrigerated merchandiser including a modular cassette refrigeration unit stowed in a compartment separate from and beneath a refrigerated interior product space of the refrigerated cabinet.

BACKGROUND OF THE INVENTION

Refrigerated merchandisers have a refrigeration system associated therewith for providing the cooled environment within a refrigerated interior product space defined within the cabinet of the refrigerated merchandiser. The refrigeration systems of such refrigerated merchandisers commonly employ a conventional refrigeration cycle and include an evaporator and an evaporator fan operatively associated with the refrigerated interior product space of the refrigerated cabinet, as well as a condenser, a condenser fan, and compressor. In stand alone cabinets, the compressor, condenser and condenser fan are housed in an equipment compartment separate from and insulated from the refrigerated interior product space of the refrigerated cabinet. A refrigerant is circulated by a compressor through refrigerant lines connecting the compressor, the condenser and the evaporator in a conventional manner to form a closed circuit. Air within the insulated refrigerated interior product space of the refrigerated cabinet is circulated by the evaporator fan through the evaporator in heat exchange relationship with the refrigerant so as to cool the air. The evaporator and evaporator fan may be disposed within the cooled interior of the refrigerated cabinet, for example in the upper region thereof.

However, it is well-known that the evaporator and evaporator fan may also be housed in the equipment compartment in a section of the equipment compartment insulated from the compressor, condenser and condenser fan. Among other uses, refrigerated merchandisers of this type may be used as product display cabinets for refrigerated or frozen foods, as vending machines, and as cold beverage merchandisers in supermarkets, grocery stores, gas stations, convenience stores, and other retail establishments. For example, cold beverages, such as soft drinks, beer, wine coolers, etc. are commonly in refrigerated merchandisers for self-service purchase by customers. Conventional beverage merchandisers of this type include an insulated cabinet defining a refrigerated interior product display space having one or more glass doors that provide access to that product display space. The beverage product, typically in cans or bottles, single or in packs, is stored on shelves within the refrigerated display zone of the cabinet. To purchase a beverage, the customer opens one of the doors and reaches into the refrigerated cabinet to retrieve the desired product from the shelf.

Refrigerated merchandisers equipped with modular refrigeration units disposed beneath the refrigerated cabinet are disclosed, for example, by Rudick et al. in U.S. Pat. Nos. 5,347,827; 5,402,654; 5,417,079; and 5,417,081. In these refrigerated merchandisers, the refrigerated air from the refrigeration unit flows up from the equipment compartment through a flow duct along the back wall of the cabinet, along the top wall of the cabinet toward the front of the cabinet and down the front of the cabinet to the floor, also referred to as the bottom deck, of the product display zone. Refrigerated air may also enter the product display zone from the rear flow duct through a plurality of openings in the panel separating the flow duct from the product display zone. The refrigerated air from the product display zone returns to the equipment compartment, entering thereto upstream of the evaporator refrigeration unit through an air return inlet opening through the cabinet floor.

The refrigeration unit disclosed therein includes an evaporator, condenser and compressor collectively arranged on a base supported on a plurality of skids affixed to the bottom of the base. The compressor and condenser are positioned on the front portion of the base, and are separated from the evaporator by an insulated vertical partition disposed therebetween. The partition includes a compliant seal on the evaporator side of the partition that abuts the cabinet for sealing the evaporator side of the refrigerant unit in communication with the refrigerated space within the cabinet.

In refrigerated merchandisers having air inlets and outlets in the wall separating the refrigerated interior product space and the equipment compartment therebeneath, the refrigeration unit needs to be effectively sealed in relation to that separation wall to ensure efficient refrigeration operation. Without an effective seal, return air could leak from the inlet duct to the outlet duct, thus bypassing the evaporator and reducing the efficiency of the refrigeration operation. Additionally, air could leak into the return air duct from the ambient air stream passing into the condenser which would increase the workload on the evaporator.

SUMMARY OF THE INVENTION

It is an object of the invention to provide an effective seal established between a refrigeration unit cassette and a refrigerated interior product space of a refrigerated merchandiser.

It is an object of one aspect of the invention to provide a lifting apparatus for locking a refrigerated unit cassette in sealing relationship with a wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette.

It is an object of one aspect of the invention to provide a lifting mechanism for positioning a refrigerated unit cassette in a first position where the cassette is in sealing relationship with a wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette and in a second position where the cassette is released from that sealing relationship to facilitate removal from the equipment compartment.

A refrigerated merchandiser is provided having a cabinet having a top wall, a lower wall, a rear wall, and side walls defining an interior space housing a product in a refrigerated environment intended for selection by consumers. A refrigeration unit cassette is disposed in operative association with the interior space in an equipment compartment separated from the refrigerated interior space by a common wall. A first opening in the common wall provides an air return inlet establishing a flow passage from the refrigerated interior space to an evaporator housed in the refrigeration unit cassette disposed in the equipment compartment beneath the lower wall. A second opening may be provided in the common wall to provide an inlet to an air supply duct for directing refrigerated air from the equipment compartment into the refrigerated interior space. A sealing system is provided having a sealing member positioned between the common wall and the refrigeration unit cassette, and a positioning apparatus for placing the refrigerated unit cassette in sealing relationship with the common wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette. In one embodiment, the sealing member may be a compressible seal which may be mounted to the common wall or may be carried on a surface of the refrigeration unit cassette.

In a further aspect of the invention, the positioning apparatus is positionable in a first position for positioning the refrigerated unit cassette into sealing relationship with the common wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette, and is positionable in a second position for releasing the refrigerated unit cassette from its sealing relationship with the common wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette.

In an embodiment, the lower wall of the cabinet forms the common wall separating the refrigerated interior space and the equipment compartment wherein the refrigeration unit cassette is housed. In this embodiment, the positioning apparatus is a lifting apparatus for selectively raising and lowering the refrigeration unit cassette. The lifting apparatus may comprise a cam mechanism selectively positionable in a first position for positioning the refrigerated unit cassette into sealing relationship with the lower wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette, and is positionable in a second position for releasing the refrigerated unit cassette from its sealing relationship with the lower wall to facilitate removal of the refrigeration unit cassette from the equipment compartment.

In a one particular embodiment of the invention, the lifting apparatus is a pair of generally L-shaped members, one operatively associated with one side of the refrigeration unit cassette and the other operatively associated with the opposite side of the refrigeration unit cassette. Each generally L-shaped member has a first elongated leg extending along its respective side of the refrigeration unit cassette and includes at least one cam section therealong. The cam section may comprise a raised portion of the first leg. Each generally L-shaped member has a second leg outwardly from an end of the first leg in a second plane that is substantially perpendicular to a first plane in which the first leg and its raised portion lie. Each generally L-shaped member may be positioned in a first position for rotating the at least one cam section so as to raise the refrigeration unit cassette upwardly to compress the compressible seal between the refrigeration unit cassette and the lower wall thereby establishing the sealing relationship. Each generally L-shaped member may be positioned in a second position for rotating the at least one cam section so as to lower the refrigeration unit cassette downwardly to release the refrigeration unit cassette from sealing relationship with the lower wall. A flat surface may be provided on the surface of the raised portion of the first elongated leg contacting the refrigeration unit cassette when in the locked position.

In another embodiment of the invention, the lifting apparatus is a pair of cam sets, one set operatively associated with one side of the refrigeration unit cassette and the other operatively associated with the opposite side of the refrigeration unit cassette. Each cam set comprises at least two cam members disposed in spaced relationship and operatively interconnected by a linkage mechanism. Each linkage mechanism may be positioned in a first position for pivoting the cam members so as to raise the refrigeration unit cassette upwardly to compress the compressible seal between the refrigeration unit cassette and the lower wall thereby establishing the sealing relationship. Each linkage may be positioned in a second position for pivoting the cam members so as to lower the refrigeration unit cassette downwardly to release the refrigeration unit cassette from sealing relationship with the lower wall.

BRIEF DESCRIPTION OF THE DRAWINGS

For a further understanding of these and objects of the invention, reference will be made to the following detailed description of the invention which is to be read in connection with the accompanying drawing, where:

FIG. 1 is a sectioned side elevation view of a refrigerated merchandiser equipped with a sealing system in accord with the invention;

FIG. 2 is a sectional side elevation view taken along line 2-2 of FIG. 1;

FIG. 3 is a perspective view of a refrigeration unit cassette showing a sealing member in accordance with the invention;

FIG. 4 is a front elevation view showing an embodiment of a positioning apparatus in accord with the present invention disposed in a first position;

FIG. 5 is a front elevation view showing the positioning apparatus of FIG. 4 disposed in a second position;

FIG. 6A and 6B are side elevation views of another embodiment of a positioning apparatus in accordance with the invention;

FIG. 7 is a front elevation view of the positioning apparatus of FIG. 6A operatively associated with a refrigeration unit cassette;

FIG. 8 is a front elevation view of the positioning apparatus of FIG. 6B operatively associated with a refrigeration unit cassette; and

FIG. 9 is a perspective view illustrating the locking of the positioning apparatus of FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGS. 1 and 2 in particular, there is depicted a refrigerated cold beverage merchandiser, designated generally by the reference numeral 10, including an interior product display space 100 for holding product 110 to be purchased, such as for example bottled or canned soda, milk, water, juices, fruit drinks, beer and other beverages. Although the invention will be described herein with reference to the depicted embodiment of a refrigerated cold beverage merchandiser, it is to be understood that that invention may be applied to other refrigerated display merchandisers for displaying perishable and frozen comestibles and beverages, including for example meats, poultry, fish, diary products, prepackaged frozen foods, and other products that need to be maintained in a controlled environment.

The beverage merchandiser 10 includes a cabinet 20 housing a refrigerated interior product display space 100 and a separate equipment compartment 55 disposed separate from, and may be heat transfer insulated from, the refrigerated interior product display space 100. The cabinet 20 has a top wall 22 and a surrounding side wall structure including a rear wall 34, a front wall 32, and opposed generally vertically extending side walls 36 and 38. The cabinet also includes a lower wall 24 disposed between the refrigerated interior product display space 100 located thereabove and the equipment compartment 55 located there beneath. The interior product display space 100 may be accessed from exteriorly of the cabinet 20 through an access opening, which in the depicted embodiment is an open area at the front of the cabinet. This open area may be open to the environment or may be covered, as in the depicted embodiment, by at least one door 40 mounted to the cabinet 20. The door 40 extends across the open area and has a transparent viewing area, for example a glass panel, through which at least a portion of the interior product display space 100 can be viewed. The door 40 is selectively positionable between a closed position covering the open area and an open position in which consumers may access the interior product display space 100 to remove a product for purchase. Although the embodiment of the display merchandiser 10 depicted in the drawing has only one door 40, it is to be understood that the display merchandiser may have one, two, three or more doors that collectively cover the open area when in the closed position. The door or doors 40 may be mounted to the cabinet 20 in a conventional manner, for example on hinges for pivotal movement or on a track for sliding movement between an open and closed position.

In the depicted embodiment, the top wall 22, the lower wall 24, rear wall 34 and the side walls 36 and 38 are heat transfer insulated for insulating the refrigerated interior product display space 100, from the environment exterior of the interior product display space 100. A plurality of shelves 112 are disposed within the interior product display space 100. The shelves 112 are adapted as appropriate to support the particular product being displayed for purchase. The specific number, arrangement and configuration of the shelves 112 is not germane to the invention and is within the skill of one of ordinary skill in the art to select for the particular product being displayed.

A rear panel 134 is provided spaced inwardly of the rear side wall 34 to establish, in part, a refrigerated air supply duct 104 between the rear side wall 34 and a rear panel 134. The interior product display space 100 within the refrigerated interior of the display cabinet 20 is bounded by the top wall 22, the lower wall 24, the side walls 36, 38, and in part by each of the rear wall 34 and the rear panel 134. In the depicted embodiment, refrigerated air enters into the product display space 100 to cool product displayed therein in part through an air outlet 109 at the upper end of the air supply duct 104 and in part through a plurality of openings 135 provided in the rear panel 134. Refrigerated air exits the product display space 100 through an opening 102 provided in the lower wall 24.

The equipment compartment 55 is located within the cabinet 20 beneath the lower wall 24 and is separated by the lower wall 24 from the refrigerated interior product display space 100 of the cabinet 20. The lower wall 24 forms a common wall separating the refrigerated interior space and the equipment compartment and has an under surface that faces the refrigeration unit cassette 50 of the refrigeration unit 15 housed within the equipment compartment. The refrigeration unit 15 includes an evaporator 60 and at least one associated evaporator fan/motor assembly 62, a condenser 70 and at least one associated condenser fan/motor assembly 72, and a compressor 74. The evaporator 60 and its associated evaporator fan/motor assembly 62 are housed within a first section 53 of the refrigeration unit cassette 50 which is separated by division wall 68 from a second section 57 of the refrigeration unit cassette 50 wherein the condenser 70, its associated condenser fan/motor assembly 72 and the compressor 74 are housed.

Referring now also to FIG. 3, the refrigeration unit cassette 50 comprises a generally rectangular box—like structure having a top plate 52, a base plate 54, and a surrounding wall structure56 extending generally vertically between the top plate 52 and the base plate 54 formed of a front plate 56A, a back plate 56B, and opposed side plates 56C. The division wall 68 extends between the opposed side plates 56C from a forward region of the top plate 52 to the back plate 56B to separate the interior of the refrigeration unit cassette 50 into the aforementioned first section 53 and second section 57. The condenser 70, its associated condenser fan/motor assembly 72, and the compressor 74 are mounted to the base plate 54 which forms the floor of the cassette refrigeration unit 50. The base plate 54 may be slidably mounted within the compartment 55 for selective disposition into and out of the compartment 55 in order to facilitate servicing of the refrigeration equipment mounted thereon. A condensate tray 76 may be provided to collect condensate dripping from the evaporator 60.

The evaporator 60, the condenser 70 and the compressor 74 are coupled in a closed—loop refrigerant circulation circuit (not shown) in a conventional manner for refrigerating air from the interior product display space 100. The condenser fan/motor assembly 72, typically a single fan and motor, is operative, typically only when the compressor 74 is in operation, to draw air from outside the refrigerated merchandiser 10, such as for example from the ambient environment external thereof through the front grille 12 provided in the lower front wall 32 of the cabinet 20, through an opening 59 provided in the front plate 56A and through the condenser 70. As the external air passes through the condenser 70 in heat exchange relationship with the refrigerant being passed therethrough by the compressor 74, the refrigerant is cooled and the air heated. Having traversed the condenser 70, the hot air is exhausted out of the compartment 55 to return to the external environment through exhaust channel 67 from beneath the first section 53 in the aft portion of second section 57 of the cassette 50. A portion of the air drawn through the cassette 50 passes over the compressor 74 to assist in cooling the compressor.

The chilled refrigerant is circulated from the condenser 70 through the closed-loop refrigerant circulation circuit (not shown) to the evaporator 60. The evaporator fan/motor assembly 62, which may be a single fan and motor or a plurality of fans with associated motors, is operative to draw air into the first section 53 of the refrigeration unit 50, also referred to as the evaporator compartment, from the interior product display space 100 through the air return inlet opening 102 in the lower wall 24 and thence pass the air through the evaporator 60 to and through the refrigerated air supply duct 104 to return to the product display space 100. As the circulating air passes through the evaporator 60, the air is cooled as it passes in heat exchange relationship with the chilled refrigerant circulated through the evaporator 60 by the compressor 74 and the refrigerant is heated and evaporated. The evaporator fan 62 circulates refrigerated air having traversed the evaporator 60 from the evaporator compartment 53 back into the refrigerated interior product display space 100 through a return air outlet 108 located in the lower wall.24 aft of rear panel 134 and into refrigerated air supply duct 104.

A cover plate 120 may be disposed over the return air inlet 102 in spaced relationship with and superadjacent the base wall 24 thereby forming flow passage between the cover plate 120 and the base wall 24 through which refrigerated air returning from the product display space 100 flows into the air return inlet 102. The cover plate 120 covers the air return inlet 102, thereby causing the downwardly directed refrigerated air to flow outwardly toward the surrounding walls of the cabinet as the refrigerated air approaches the lower region of the product display space 100 in order to pass beneath the cover plate 120 into the air return inlet 102 in the lower wall 24. In doing so, the refrigerated air passes through the product on the lower shelves to more evenly cool that product and to block the refrigerated air from funneling downwardly directly into the return air return inlet 102. The cover plate 120 also restricts the flow of spills or leaks from product in the product display space 100 from flowing directly into the evaporator compartment 53 and fouling the evaporator and/or evaporator fan assembly.

In one embodiment, the cover plate 120 includes a circumferential flange 126 extending generally vertically downwardly therefrom to the base wall 24 for supporting the cover plate 120 over the air return inlet 102 in the base wall 124. A plurality of circumferentially spaced openings 125 are provided in the circumferential flange 126 to form the air flow passage connecting the refrigerated interior space 25 in flow communication with the air return inlet 102 to the evaporator compartment 53 of the refrigeration unit cassette 50.

A sealing system is provided including a sealing member 58 positioned between the lower wall 24 and the refrigeration unit cassette 50 and a positioning apparatus 150 for placing the refrigeration unit cassette 50 into sealing relationship with the common wall, which in the depicted embodiment is the lower wall 24 that separates the refrigerated interior product display space 100 from the equipment compartment 55. The sealing system prevents refrigerated air returning to the refrigeration unit 15 from the product display space 100 from bypassing the evaporator 60 and instead flowing directly into the inlet 108 to the air supply duct 104 from the air return inlet 102. The sealing system also prevents ambient air from externally of the refrigeration unit cassette 50, such as the ambient air that has been drawn through the front grille 12 to pass through the condenser 70, from being drawn into the refrigerated air returning to the refrigeration unit 15 through the air return inlet 102 in the lower wall 24.

The sealing member 58 may be mounted to the under surface of the lower wall 24 about the opening 102 in the lower wall 24, or may be mounted or simply carried upon to the upper surface of the top plate 52 of the refrigeration unit cassette 50. The sealing member 58 extends at least about the opening 51A in the top plate 52, as illustrated in FIG. 3, which is substantially commensurate with the opening 102 in the lower wall 24. The sealing member 58 also may extend about the opening 51B, which is provided in the top plate 52 rearward of the opening 51, as illustrated in FIG. 3, and which opens in flow communication with the opening 108 in the lower wall 24. That is, in the depicted embodiment the sealing member 58 takes the form of a rectangular frame with a cross member similar to a double hung window frame.

The sealing member 58 may comprise one or more compressible seals provided on the refrigeration unit cassette 50 which are compressed against the lower wall 24 when the cassette refrigeration unit 50 is raised within the compartment 55 by operation of the positioning apparatus 150. However, the sealing member 58 may also comprise one or more non-compressible seals, such as contact seals, that coact with the respective opposing surfaces of the refrigeration unit cassette and of the common wall separating the refrigerated interior space from the equipment compartment and surrounding the respective openings therein to provide the desired sealing arrangement therebetween when the cassette refrigeration unit 50 is positioned by operation of the lifting apparatus 150 to sandwich the sealing member 58 therebetween.

In the exemplary embodiment depicted, the positioning apparatus is a lifting apparatus 150 that is positionable in a first position for raising the refrigerated unit cassette into sealing relationship with the lower wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette, and is positionable in a second position for lowering the refrigerated unit cassette from its sealing relationship with the lower wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette. The lifting mechanism may comprise a cam mechanism selectively positionable in a first position, as illustrated in FIG. 4, for positioning the refrigerated unit cassette into sealing relationship with the lower wall separating the refrigerated interior product space from an equipment compartment housing the refrigeration unit cassette, and is positionable in a second position, as illustrated in FIG. 5, for releasing the refrigerated unit cassette from its sealing relationship with the lower wall to facilitate removal of the refrigeration unit cassette from the equipment compartment

Referring now to FIGS. 4 and 5, in the particular embodiment depicted, the lifting apparatus 150 is a pair of generally L-shaped members 152, one operatively associated with one side of the refrigeration unit cassette and the other operatively associated with the opposite side of the refrigeration unit cassette. Each generally L-shaped member has a first elongated leg 154 extending along its respective side of the refrigeration unit cassette and includes at least one cam 155 section therealong. The cam section 155 may comprise a raised portion of the first leg 154. Each generally L-shaped member 152 has a second leg 156 extending outwardly from an end of the first leg 154 in a second plane that is generally perpendicular to a first plane in which the first leg 154 and its raised cam section 155. The generally L-shaped members 152 may be formed from ⅜ inch diameter, zinc-plated carbon steel rod, but may also be formed of equivalent materials possessing adequate strength and corrosion resistant characteristics.

When the refrigeration unit cassette 50 is installed within the equipment 55 and placed in its operational position, each of the generally L-shaped members 152 is positioned in a first position, as illustrated in FIG. 4, wherein the cam sections 155 extend upwardly so as to raise the refrigeration unit cassette upwardly to compress the compressible seal 58 between the top plate 52 of the refrigeration unit cassette 50 and the undersurface of the lower wall 24 thereby establishing the sealing relationship. In this position, the second leg 156 is generally horizontally disposed so as to extend inwardly toward the other member 152 and partially across the lower portion of the access opening to the equipment compartment 55 and in front of the refrigeration unit cassette 50. In this manner, the respective second legs 156 of the paired generally L-shaped members 152 serve as barriers to removal of the refrigeration unit cassette 50 when positioned in sealing relationship with the lower wall 24. Thus, the second legs 152 in effect lock the refrigeration unit cassette 50 in its sealing position and prevent removal of the cassette 50 thereby protecting the sealing member 58 from possible damage. Further, in the sealing position, the cam sections 155 on the respective first legs 154 are canted slightly off the vertical in an inwardly direction, that is generally towards each other, whereby the weight of the refrigeration cassette 50 acting downwardly on the cam sections 155 acts to rotate the respective second legs 156 downwardly and lock the cassette 50 in the sealing position. Additionally, a locking device, such as for example a cotter pin 51 inserted through holes 153 in latch studs 157 and a corresponding hole in a distal portion of the second leg 156, as illustrated in FIG. 9, may be provided to ensure the generally L-shaped members can not rotate out of position without direct action by a person accessing the unit. A flat surface may be provided on the surface of the raised cam section 155 contacting the refrigeration unit cassette when in the locked position. The first leg 154 of each member 152 is mounted to the base of the cabinet for pivotal movement, for example by means of a clamp bracket 159 or other suitable means.

When it is desired to release the refrigeration unit cassette 50 for removal for servicing, each of the generally L-shaped members 152 may be rotated into a second position wherein the second leg 156 of each extends generally upwardly and outwardly at the sides of the access opening to the equipment compartment 55 laterally of the refrigeration unit cassette 50. So positioned, the cam sections 155 will now lie flat beneath the refrigeration unit cassette 50 and the refrigeration unit cassette will move downwardly thereby releasing the refrigeration unit cassette 50 from sealing relationship with the lower wall 24 as illustrated in FIG. 5. With the generally L-shaped members 152 so positioned, the second legs 156 of the respective L-shaped members 152 are positioned to extend generally upwardly and outwardly in front of the respective side walls 36 and 38. So positioned, the service person may readily slide the refrigeration unit cassette 50, partially or fully, out of the equipment compartment 55. Further, with the second legs 156 so positioned, the front wall 32 carrying the grille 12 can not be re-installed until the refrigeration cassette 50 is inserted and lifted into its sealed position. To reinstall the grille 12, the respective second legs 156 must first be rotated inwardly, thereby lifting the refrigeration cassette into its first, i.e. sealed, position. This ensures that the refrigerated merchandiser will not be inadvertently returned to operation with the refrigeration cassette 50 inserted but not positioned in sealing relationship with the refrigerated interior of the refrigerated merchandiser.

Referring now to FIGS. 6, 7 and 8, in another embodiment of the invention, the lifting apparatus 150 may be a pair of cam sets 162, one set operatively associated with one side of the refrigeration unit cassette and the other operatively associated with the opposite side of the refrigeration unit cassette. Each cam set 162 comprises a pair of cam members 165 disposed in spaced relationship and operatively interconnected by a linkage mechanism 164. The linkage member 164 may comprise a pivot mechanism 166 located centrally between the paired cam members 165 and connected to the forward cam member by a first link bar 163 and to the rearward cam member by a second link bar 167. Each cam member 165 is mounted eccentrically to its respective link bar and has a distal end 161 such that upon rotation of the pivot mechanism 164, each cam member also rotates to position the distal end 161 thereof so as to extend generally vertically or generally horizontally, depending upon the direction of rotation.

In the depicted embodiment, when the pivot mechanism 166 of each cam set 162 is rotated clockwise, as illustrated in FIG. 6A, each cam member 165 is pivoted into a first position with its distal end 161 extending generally vertically upwardly, thereby raising the refrigeration unit cassette 50 upwardly, as illustrated in FIG. 7, so as to compress the compressible seal between the top plate 52 of the refrigeration unit cassette 50 and the lower wall 24 so as to establish the sealing relationship. A cam stop 155 may be provided to limit the pivotal movement of the cam member 165 beyond the vertical position. However, when the pivot mechanism 166 of each cam set 162 is rotated counter-clockwise, as illustrated in FIG. 6B, each cam member 165 is positioned in a second position with its distal end 161 extending generally horizontally outwardly. So positioned, the refrigeration unit cassette 50 will move downwardly thereby releasing the refrigeration unit cassette 50 from sealing relationship with the lower wall 24 as illustrated in FIG. 8. The pivot mechanism 166 of the right and left cam sets 162 may be independently operable or may be cross-linked so as to rotate together. With the distal ends 161 of the cam members 165 fully disengaged from the under surface of the refrigeration unit cassette 50, the sealing member 58 is not compressed and the cassette 150 may be withdrawn, fully or partially, from the equipment compartment 55.

In either of the aforedescribed embodiments, a roller track or other translation facilitating means may be provided within the equipment compartment 55 beneath the refrigeration unit cassette 50 to ease removal of the cassette. With the lifting apparatus 150 positioned in its first positioned, the cam members 155, 165 are positioned to extend generally vertically upwardly to engage and lift the refrigeration unit cassette 50 upwardly off the roller track and compress the compressible sealing member 58 between the top plate 52 of the refrigeration unit cassette 50 and the undersurface of the lower wall 24 thereby establishing the sealing relationship. With the lifting apparatus 150 positioned in its second position, the cam members 155, 165 are positioned to extend generally horizontally to release the refrigeration unit cassette 50 to move downwardly to contact the roller track and relax the compressible sealing member 58 as so to break the sealing relationship, thereby allowing the refrigeration unit cassette 50 to be translated along the roller track for withdrawal from the equipment compartment 55 without risk of damage to the sealing member 58.

The sealing system of the present invention has been described herein with reference to the exemplary embodiments depicted in the drawings for purposes of illustration and to facilitate understanding of the invention. Those skilled in the art will realize that modifications, some of which may have been alluded to hereinbefore, may be made to the depicted embodiments without departing from the spirit and scope of the present invention. For example, the positioning apparatus may be used to establish a sealing relationship in accordance with the present invention in conjunction with sealing members that are not compressible. Further, various other embodiments of positioning apparatus may be employed to establish a sealing relationship between the cabinet and the refrigeration unit cassette by acting upon a sealing member disposed therebetween without departing from the spirit and scope of the invention. 

1. A sealing system for a refrigerated merchandiser having a cabinet having a refrigerated interior space for housing a product in a refrigerated environment intended for selection by consumers and a having refrigeration unit cassette disposed in operative association with the interior space in an equipment compartment separated from the refrigerated interior space by a common wall, the common wall having a first opening therein providing fluid flow communication between the refrigerated interior space and the equipment compartment; the sealing system comprising: a sealing member disposed between the common wall and the refrigeration cassette unit about said first opening; and a positioning apparatus for placing the refrigeration cassette unit into sealing relationship with the common wall.
 2. A sealing system for a refrigerated merchandiser as recited in claim 1 wherein said positioning apparatus is positionable in a first position thereby placing the refrigerated unit cassette into sealing relationship with the common wall, and is positionable in a second position thereby releasing the refrigerated unit cassette from its sealing relationship with the common wall.
 3. A sealing system for a refrigerated merchandiser as recited in claim 1 wherein said sealing member comprises a compressible seal.
 4. A sealing system for a refrigerated merchandiser as recited in claim 1 wherein said positioning apparatus comprises a lifting apparatus for raising the refrigeration cassette unit into sealing relationship with the common wall.
 5. A sealing system for a refrigerated merchandiser as recited in claim 1 wherein said sealing member comprises a compressible seal and said positioning apparatus comprises a lifting apparatus for raising the refrigeration cassette unit into sealing relationship with the common wall.
 6. A sealing system for a refrigerated merchandiser as recited in claim 1 wherein said sealing member is carried on an upper surface of said refrigeration cassette.
 7. A sealing system for a refrigerated merchandiser having a cabinet having a refrigerated interior space for housing a product in a refrigerated environment intended for selection by consumers and a having refrigeration unit cassette disposed in operative association with the interior space in an equipment compartment beneath the refrigerated interior space and separated from the refrigerated interior space by a common wall, the common wall having a first opening therein providing fluid flow communication between the refrigerated interior space and the equipment compartment; the sealing system comprising: a compressible sealing member disposed between the common wall and the refrigeration unit cassette about said first opening; and a lifting apparatus disposed in operative association with the refrigeration unit cassette for raising the refrigeration unit cassette upwardly to compress said compressible sealing member against the common wall thereby establishing a sealing relationship about said first opening.
 8. A sealing system for a refrigerated merchandiser as recited in claim 7 wherein said lifting apparatus is positionable in a first position thereby raising the refrigerated unit cassette to compress said compressible sealing member, and is positionable in a second position thereby lowering the refrigerated unit cassette to decompress said sealing member.
 9. A sealing system for a refrigerated merchandiser as recited in claim 7 wherein said lifting apparatus comprises a cam mechanism selectively positionable in a first position thereby raising the refrigerated unit cassette to compress said compressible sealing member, and is positionable in a second position thereby lowering the refrigerated unit cassette to decompress said sealing member.
 10. A sealing system for a refrigerated merchandiser as recited in claim 7 wherein said lifting apparatus comprises a pair of cam sets, one cam set of the pair of cam sets operatively associated with one side of the refrigeration unit cassette and the other cam set of said pair of cam sets operatively associated with the opposite side of the refrigeration unit cassette, each cam set having at least two cam members disposed in spaced relationship and operatively interconnected by a linkage mechanism.
 11. A sealing system for a refrigerated merchandiser as recited in claim 10 wherein said linkage mechanism is positionable in a first position for pivoting said cam members so as to raise the refrigeration unit cassette upwardly to compress said compressible sealing member and is positionable in a second position for pivoting said cam members so as to lower the refrigeration unit cassette downwardly to decompress said compressible sealing member.
 12. A sealing system for a refrigerated merchandiser as recited in claim 7 wherein said lifting apparatus comprises a pair of generally L-shaped members, one member of said pair of generally L-shaped members operatively associated with one side of the refrigeration unit cassette and the other member of said pair of generally L-shaped members operatively associated with the opposite side of the refrigeration unit cassette, each member of said pair of generally L-shaped members having an elongated leg extending along a side of the refrigeration unit cassette and having at least one cam section.
 13. A sealing system for a refrigerated merchandiser as recited in claim 12 wherein said at least one cam section comprises a raised portion of the first leg.
 14. A sealing system for a refrigerated merchandiser as recited in claim 13 further comprising a flat surface on the raised portion of the first elongated leg for contacting the refrigeration unit cassette when in the first position.
 15. A sealing system for a refrigerated merchandiser as recited in claim 12 wherein said generally L-shaped member has a second leg extending outwardly from an end of the first leg in a second plane substantially perpendicular to a first plane in which the first leg and the raised portion lie.
 16. A sealing system for a refrigerated merchandiser as recited in claim 12 wherein each generally L-shaped member may be positioned in a first position for rotating said at least one cam section so as to raise the refrigeration unit cassette upwardly to compress said compressible sealing member between the refrigeration unit cassette and the common wall thereby establishing the sealing relationship.
 17. A sealing system for a refrigerated merchandiser as recited in claim 12 wherein each generally L-shaped member may be positioned in a second position for rotating said at least one cam section so as to lower the refrigeration unit cassette downwardly to decompress said compressible sealing member thereby releasing the refrigeration unit cassette from sealing relationship with the lower wall.
 18. A refrigerated merchandiser having an interior space housing a product in a refrigerated environment intended for selection by consumers, comprising: a cabinet having a top wall, a lower wall, a rear wall, and side walls defining the interior space; a refrigeration unit disposed in operative association with the interior space in a compartment beneath the lower wall and having an upper surface facing a lower surface of the lower wall; an opening in the lower wall providing an air return inlet establishing a flow passage from the interior space to the compartment beneath the lower wall; a sealing member disposed between the common wall and the refrigeration cassette unit about said first opening; and a lifting apparatus for raising the refrigeration cassette unit into sealing relationship with the lower wall.
 19. A refrigerated merchandiser as recited in claim 18 wherein said lifting apparatus is positionable in a first position thereby rising the refrigerated unit cassette into sealing relationship with the lower wall, and is positionable in a second position thereby releasing the refrigerated unit cassette from the sealing relationship with the lower wall.
 20. A refrigerated merchandiser as recited in claim 19 wherein said lifting apparatus when positioned in the second position prevents installation of a grille over an ambient air inlet to the compartment beneath the lower wall.
 21. A refrigerated merchandiser as recited in claim 18 wherein said sealing member comprises a compressible seal.
 22. A refrigerated merchandiser as recited in claim 18 wherein said sealing member is carried on an upper surface of said refrigeration cassette. 